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| Massive tornado crossing a highway in Tuscaloosa, Alabama, April 27, 2011. One of 300+ tornadoes in this outbreak Today is the tenth anniversary of arguably the worst tornado outbreak in U.S. history. |
Since April 25-28, 2011, all other tornado swarms are measured against this epic outbreak, which peaked on April 27 that year.
The storms killed 321 people, injured more than 1,200 others and caused $12 billion in property damage, making it one of the deadliest and the most costly tornado outbreak in United States history.
A whopping 350 tornadoes or so touched down in the United States during this outbreak, the most in any swarm in history. Some videos of this incredible event are at the bottom of this post.
Meanwhile up here in Vermont, the same storm system spawned our own smaller, but still very significant disaster in the form of a destructive flash flood that also greatly contributed to a record flood crest on Lake Champlain. More on Vermont's issues that week further down in this post.
The tornado outbreak of 2011 easily outdid the previous record for a tornado outbreak in the United States, one that produced 148 tornadoes in April, 1974.
If you combined all the paths of the tornadoes in the 2011 outbreak into one continuous string, it would extend 3,200 miles. The part of the nation hit by tornadoes was immense, too, extending from central Texas to central New York.
The tornado outbreak was especially notable for the number of strong and extreme tornadoes in produced, especially in Alabama. That state suffered 240 of the tornado deaths attributed to the outbreak.
Fifteen of the tornadoes were rated EF-4 or EF-5, the strongest possible. It's rare to get as many as three or four tornadoes that strong in a single outbreak.
These strongest tornadoes also traveled great distances at high speeds, making them especially deadly. The Weather Channel says the average path length of the 15 strongest tornadoes was 65 miles, and they had a forward speed of between 45 and 70 mph.
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| Red dots depict all the tornado reports just on April 27, 2011 and don't include the reports on the previous two days and the day after. |
As you can imagine, debris was scattered far and wide by this tornado swarm.
A photograph sucked up by an EF-5 tornado in Phil Campbell, Alabama was later found 220 miles away in Tennessee. A jacket picked up by a tornado in Hackleburg, Alabama was later found 68 miles away.
The most famous of the many tornadoes in this outbreak was a monster EF-4 that traveled an 80-mile long path through Tuscaloosa, Alabama through the northwestern suburbs of Birmingham, killing in total 65 people.
That is a very, very long track for a tornado. The parent tornadic supercell thunderstorm held together for an incredible 380 miles from southeastern Mississippi to western North Carolina.
The tornadoes were unrelenting, especially in and around Alabama, which suffered at least three rounds of destructive tornadoes. The town of Cordova, Alabama was struck by two strong EF3 tornadoes on April 27, 2011, one early in the morning and the other during the afternoon.
Today, the 10th anniversary of this disaster, is surely a somber day, especially in Alabama.
VERMONT IMPACTS
Vermont escaped the tornadoes of April, 2011, with the closest one touching down west of Albany. Instead, we got a destructive flood, one of several in that devastating year of 2011.
Snowpack in Vermont in the early spring of 2011 was at near record high levels, especially in the mountains. The month of April leading up to this event was very wet. There had already been one damaging flood a couple weeks before this event.
Even before the April 26-27 storm, Lake Champlain was well above flood stage.
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| Severe flooding along the Lamoille River near Cambridge, Vermont on April 27, 2011. Major damage from flooding in much of Vermont that day |
The days leading up to this flood were also quite warm, which primed the pump by softening and melting all that mountain snow.
An initial round of showers and some thunderstorms associated with the storm and tornado outbreak came through Vermont early on April 25, sending rivers close to bank full.
Then, in the evening and overnight hours of April 26, repeated, heavy early season thunderstorms rolled over Vermont. Some were almost severe, which is odd for so early in the season. For instance, St. Albans was barraged by a lot of dime sized hail in one storm.
More importantly, these storms contained torrential downpours. Two to five inches of rain fell on northern and central Vermont, especially around the Lamoille River Valley. That evening and overnight, flash flooding from small creeks and streams roared out of the mountains and into northern Vermont towns.
A little stream by my house in St. Albans, normally a few inches deep at most, was suddenly five feet deep. It caused flash flood damage on my property via washouts and debris flows. I've never had anything close to a flash flood before or since that event.
The Lamoille River went into major flood, with one of the highest crests on record. Dozens of homes and businesses flooded, especially in Johnson and Jeffersonville. Northeast New York and northern Vermont were declared major disaster areas, as flood damage exceeded $9 million.
The water from this flooding inevitably flowed into Lake Champlain, forcing the lake into its highest crest on record, 103.2 feet on May 6, which of course created yet another multi-million dollar flood disaster.
ECHO WEATHER PATTERN
Interestingly, the weather pattern this week is vaguely similar to that of late April, 2011, but the ingredients certainly are NOT there for a repeat of that calamity ten years ago. A few tornadoes might spin up in the Plains and Midwest today and tomorrow. A brief twister could conceivably even touch down in western New York tomorrow.
But this week's rough weather will be a typical spring severe storm episode, and won't be especially noteworthy.
A nearly stalled weather front will also waver near Vermont this week, much as one did on April 26-27, 2011.
Very much unlike ten years ago, the weather front this week will produce only a moderate amount of rain. This rainfall will do far more good than harm, and won't lead to flooding. The expected rains later this week will help put a dent in Vermont's lingering drought.
Videos:
Terrifying television tornado coverage by legendary Alabama meteorologist James Spann as the giant tornado roared into Tuscaloosa:
An even scarier close up view of the Tuscaloosa tornado as it roars past an apartment:
Excellent overview of tornadoes/destruction in Alabama from ABC 33/40, which is Spann's television station:
Finally, a video I took of powerful floodwaters along the Lamoille River near Cambridge, Vermont on April 27, 2011.
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